22 research outputs found
Effects of β2-receptor stimulation by indacaterol in chronic heart failure treated with selective or non-selective β-blockers: a randomized trial
Alveolar \u3b22-receptor blockade worsens lung diffusion in heart failure (HF). This effect could be mitigated by stimulating alveolar \u3b22-receptors. We investigated the safety and the effects of indacaterol on lung diffusion, lung mechanics, sleep respiratory behavior, cardiac rhythm, welfare, and exercise performance in HF patients treated with a selective (bisoprolol) or a non-selective (carvedilol) \u3b2-blocker. Study procedures were performed before and after indacaterol and placebo treatments according to a cross-over, randomized, double-blind protocol in forty-four patients (27 on bisoprolol and 17 on carvedilol). No differences between indacaterol and placebo were observed in the whole population except for a significantly higher VE/VCO2 slope and lower maximal PETCO2 during exercise with indacaterol, entirely due to the difference in the bisoprolol group (VE/VCO2 31.8\u2009\ub1\u20095.9 vs. 28.5\u2009\ub1\u20095.6, p\u2009<\u20090.0001 and maximal PETCO2 36.7\u2009\ub1\u20095.5 vs. 37.7\u2009\ub1\u20095.8\u2009mmHg, p\u2009<\u20090.02 with indacaterol and placebo, respectively). In carvedilol, indacaterol was associated with a higher peak heart rate (119\u2009\ub1\u200934 vs. 113\u2009\ub1\u200930 bpm, with indacaterol and placebo) and a lower prevalence of hypopnea during sleep (3.8 [0.0;6.3] vs. 5.8 [2.9;10.5] events/hour, with indacaterol and placebo). Inhaled indacaterol is well tolerated in HF patients, it does not influence lung diffusion, and, in bisoprolol, it increases ventilation response to exercise
Prosthetic mitral valve thrombosis: can fluoroscopy predict the efficacy of thrombolytic treatment?
Thrombolysis (T) is an effective therapy for prosthetic valve thrombosis (PVT). Debate still exists as to which clinical or noninvasive finding best predict the result of T. The aim of the study was to investigate the role of fluoroscopy (F) to predict efficacy of T in pts with mitral PVT
Improvement of alveolar-capillary membrane diffusing capacity with enalapril in chronic heart failure and counteracting effect of aspirin
KII ACE, the enzyme that converts angiotensin I and inactivates bradykinin, is highly concentrated in the lungs; its blockade reduces exposure to angiotensin II and enhances exposure to prostaglandins generated by local kinin hyperconcentration. Our hypothesis is that ACE inhibitors improve pulmonary function in chronic heart failure (CHF) by readjusting lung vessel tone and permeability or alveolar-capillary membrane diffusion
Acute blood pressure reduction in the presence of hypertensive cardiac hypertrophy: any interference with coronary circulation?
Three-dimensional echocardiography in valve disease
This review covers the role of three-dimensional (3D) echocardiography in the diagnosis of heart valve disease. Several factors have contributed to the evolution of this technique, which is currently a simple and routine method: rapid evolution in probe and computer technologies, demonstration that 3D data sets allowed more complete and accurate evaluation of cardiac structures, emerging clinical experience indicating the strong potential particularly in valve diseases, volume and function of the two ventricle measurements and several other fields. This report will review current and future applications of 3D echocardiography in mitral, aortic and tricuspid valve diseases underlying both qualitative (morphologic) and quantitative advantages of this technique
Exercise performance in patients with uncomplicated essential hypertension. Effects of nifedipine-induced acute blood pressure reduction
In untreated patients with uncomplicated essential hypertension, exercise induces an abnormal increase in blood pressure; the influences of this increase on exercise were evaluated by a cardiopulmonary exercise test (CPX) performed in control conditions (step 1) and during acute blood pressure reduction (step 2). Patients were classified as (1) normotensive (resting diastolic blood pressure [BPd] less than 90 mm Hg; n = 14), (2) mildly hypertensive (BPd of 90 to 104 mm Hg; n = 9), and (3) moderately to severely hypertensive (BPd greater than or equal to 105 mm Hg; n = 16). For the three groups, peak mean blood pressure during exercise was 125 +/- 5 mm Hg (mean +/- SEM), 144 +/- 3 mm Hg (p less than 0.01 vs normotensive), and 161 +/- 4 mm Hg (p less than 0.01 vs normotensive and p less than 0.01 vs mild hypertension), respectively. Oxygen consumption (VO2) at peak exercise and at ventilatory anaerobic threshold was 26.1 +/- 1.1 and 17.2 +/- 0.5 ml/min/kg, 25.4 +/- 1.1 and 16.9 +/- 0.8 ml/min/kg, and 26.4 +/- 1.3 and 17.5 +/- 1.2 ml/min/kg in normotensive subjects, those with mild hypertension, and those with moderate to severe hypertension, respectively. Fourteen normotensive subjects, six with mild hypertension, and nine with moderate to severe hypertension participated to step 2 (nifedipine vs placebo, double-blind crossover). Nifedipine reduced blood pressure at rest and at peak exercise in those with hypertension. Peak exercise VO2 was unaffected by nifedipine in both normotensive subjects and those with hypertension. With nifedipine, ventilatory anaerobic threshold occurred earlier and at a lower VO2 in mild and in moderate to severe hypertension (delta VO2 = -1.9 and -2.4 ml/min/kg, respectively). These findings might be due to nifedipine-induced redistribution of blood flow during exercise and might be the reason for the complaint of weakness after blood pressure reduction in hypertensive subjects
Modification of exercise performance by sharp reduction of blood pressure. A study in patients with uncomplicated hypertension
We evaluated exercise performance in 14 patients with uncomplicated essential hypertension 1 h after the administration of a single dose of placebo, nifedipine (20 mg), captopril (50 mg), and propranolol (80 mg). Drugs were administered at the same time of day following a randomized, double-blind protocol. Mean resting blood pressure (+/- SE) was 135 +/- 3 mm Hg with placebo administration, 118 +/- 4 with captopril, 110 +/- 4 with nifedipine, and 115 +/- 5 with propranolol and increased with exercise to 163 +/- 4, 146 +/- 3, 136 +/- 4, 136 +/- 4, respectively. Oxygen consumption at peak exercise and at ventilatory anaerobic threshold (VAT) was 25.2 +/- 1.1 and 18.1 +/- 1.0 ml/min/kg with placebo. Only propranolol (-2.3 ml/min/kg) decreased peak exercise oxygen consumption. Oxygen consumption at VAT was reduced by nifedipine and propranolol but unaffected by captopril. The effects on exercise capacity of blood pressure reduction in hypertensive patients are dependent on the drug utilized and are not related to the amount of blood pressure reduction. The lowered oxygen consumption at VAT observed with nifedipine and propranolol, and not with captopril, might be due to an excessive downward shift of the muscle perfusion pressure--oxygen consumption relationship which might take place during exercise